Marker peptide screening and species-specific authentication of Pheretima using proteomics.

Pheretima is a common and valuable animal-derived medication used in traditional Chinese medicine. There are four species of Pheretima specified in the Chinese Pharmacopoeia (2015 edition), i.e. Pheretima aspergillum, P. vulgaris, P. guillelmi, and P. pectinifera. A recent report revealed ~ 55% of Pheretima in the commercial marketplace may be adulterated by other species, contrary to the Pharmacopoeia standard. The safety, efficacy, and authenticity of Pheretima is an important issue. Currently, the availability of specific quality-markers for the various species and effective identification methods are still limited. In this study, label-free quantification proteomics of species from Pheretima and Amynthas was carried out using nanoscale liquid chromatography coupled to tandem mass spectrometry (nano LC-MS/MS), and marker peptides were identified based on their ion intensities using multivariate data analysis (principal component analysis and supervised partial least-squares discriminant analysis). A total of 48,476 peptides with high confidence corresponding to 13,397 proteins were identified from all samples. The marker peptides were validated by comparison with synthetic peptide reference standards using LC-MS/MS operating in a multiple-reaction monitoring mode. A multiple-peptide identification strategy was proposed for the authentication of Pheretima and subsequently applied to samples obtained from retail outlets in various regions of China. The results showed that eight out of the 15 samples tested were deemed authentic Pheretima.

Isolation and identification of a new sildenafil analogue, hydroxycarbodenafil, found as an adulterant in a health supplement.

During routine screening of illegal adulterants in health supplements, a novel sildenafil analogue was discovered, and subsequently isolated by recrystallization. Its structure was elucidated by extensive analyses of high resolution mass spectrometry (HRMS), one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) data. The analogue was finally determined as hydroxycarbodenafil, featuring a hydroxyethyl group instead of an ethyl group on piperazine ring in comparison with carbodenafil.

LC-MS-guided isolation of anti-inflammatory 2-(2-phenylethyl)chromone dimers from Chinese agarwood (Aquilaria sinensis).

Fifteen previously undescribed 2-(2-phenylethyl)chromone dimers, along with two known analogues were isolated from Chinese agarwood (Aquilaria sinensis) by a LC-MS-guided fractionation procedure. Their structures were elucidated on the basis of spectroscopic and spectrometric data (1D and 2D NMR, IR, and HRESIMS). The isolated compounds exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells with IC50 values in the range 0.6-37.1 µM.

Anti-inflammatory 2-(2-phenylethyl)chromone derivatives from Chinese agarwood.

Five new 2-(2-phenylethyl)chromone derivatives (1-5), along with eleven known compounds (6-16) were isolated from Chinese agarwood. Their structures were elucidated by spectroscopic data (NMR, UV, IR, and MS) analyses and comparison of their spectroscopic and physical data with the literature values. The absolute configurations of 2-4 were determined by electronic circular dichroism (ECD) calculations. Compounds 2-4, 11, 12, and 15 exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 cells with IC50 values in the range 1.6-7.3µM.

[HPLC determination of two phenylpropanoid amides in solani melongenae radix from different cultivation regions].

A quantitative HPLC-DAD method was developed for simultaneous determination of N-trans-p-coumaroyloctopamine and N-trans-p-coumaroyltyramine in Solani Melongenae Radix from different cultivation regions in China The separation was performed on an Agilent Eclipse XDB C18 column (4.6 mm x 250 mm, 5 microm) at 30 degrees C with a gradient elution of methanol and 0.1% formic acid in water as mobile phase. The flow rate was set at 1.0 mL x min(-1) and the detection wavelength was 300 nm. The calibration curves of N-trans-p-coumaroyloctopamine and N-trans-p-coumaroyltyramine were linear over the ranges of 2.84-68.16, 3.10-74.40 mg x L(-1), and the average recoveries (n = 9) were 99.30% and 102.8%, respectively. The developed method was successfully applied for the analysis of sixteen samples from different cultivation regions in China, which indicated that the method is simple, rapid, accurate, and reliable for quality evaluation of Solani Melongenae Radix.

Anti-inflammatory ursane- and oleanane-type triterpenoids from Vitex negundo var. cannabifolia.

Six new polyoxygenated triterpenoids, cannabifolins A-F (1-6), and eight known triterpenoids, 7-14, were isolated from the leaves of Vitex negundo var. cannabifolia. The absolute configuration of cannabifolin A (1) was determined by single-crystal X-ray crystallographic analysis. Compounds 1 and 2 represent a class of rare natural pentacyclic triterpenoids bearing cis-fused C/D rings and are the first examples of 12,19-epoxy ursane- and oleanane-type triterpenoids. Compounds 3, 7, 8, and 14 exhibited inhibition of nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages with IC50 values in the range 24.9-40.5 µM.

Anti-inflammatory lignanamides from the roots of Solanum melongena L.

Four new lignanamides, melongenamides A-D (1-4), together with six known ones (5-10), were isolated from the roots of Solanum melongena L. Their structures were elucidated on the basis of 1D and 2D NMR experiments and by comparison of their spectroscopic and physical data with the literature values. Compounds 2-8 exhibited inhibitions of nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages with IC50 values ranging from 16.2 to 58.5 µM.

Anti-inflammatory labdane diterpenoids from Lagopsis supina.

Ten new labdane diterpenoids, lagopsins A-H (1-3, 5, 7-10) and 15-epi-lagopsins C and D (4, 6), together with five known labdane diterpenoids (11-15), were isolated from the whole plants of Lagopsis supina. The absolute configuration of lagopsin A (1) was determined by single-crystal X-ray crystallographic analysis. Compounds 7, 9, 13, and 15 exhibited moderate inhibition of nitric oxide production stimulated by lipopolysaccharide in BV-2 microglial cells with IC50 values in the range 14.9-34.9 µM.